(CNN) — Pilgrimages aren't only for the religious.
They can be fun and inspiring, challenging yet rewarding and don't necessarily involve prayer.
The best ones, however, do involve a bit of a trek.
Even if don't "find yourself" along the way, you'll definitely find something to tell your friends about once you get back.
Kumano Ancient Trail (Japan)
Popularized by emperors in the 10th century, the trail to Kumano leads to three sacred shrines, numerous protector shrines and tea houses.
Located in the Kii mountains south of Osaka, the views are often spectacular. You can walk for days or weeks -- it's up to you. You can do the whole pilgrimage in roughly six weeks.
A hot spring hotel to soothe aches and pains at the end of the day is never far away. This is one of only two UNESCO-recognized pilgrimage walks, after the Camino de Santiago in Spain.
Getting there: Best time to go is in spring and fall. Fly to Kansai International airport, Osaka and take a train to Kii-Tanabe station. From there you can ride a bus to the pilgrimage route trailhead.
Inca Trail to Machu Picchu (Peru)
Billed by some as a life-changing experience, experts believe the Incas built this trail as a holy pilgrimage to prepare visitors to enter Machu Picchu.
The 43-kilometer (26.7 miles) walk can be challenging, partly due to the high altitude and rough terrain.
Access to the trail is strictly controlled, with the Peruvian government issuing 500 permits each day -- about 200 of these are for tourists. The rest go to guides, porters and cooks.
Make sure you book well ahead and organize your trip through an authorized trekking company.
Getting there: Best time to go is May through September. The trail starts in Cusco, an expensive one-hour flight or inexpensive 21-hour bus ride from Lima.
Mount Kailash Pilgrimage (Tibet)
Mount Kailash in Tibet has been a popular destination among pilgrims for more than 15,000 years.
Supposedly the pilgrimage can erase the sins of a lifetime.
It takes roughly three days to trek the 52-kilometer (32.3 miles) trail around the mountain. Climbing it is forbidden.
According to Buddhist teachings, if you manage to keep going for 108 rounds, you'll reach Nirvana.
Getting there: Best time to go is April through September. A tour company can help with the logistics of getting into Tibet and driving to the base of Mount Kailash.
Camino de Santiago (Spain)
Also known as The Way of St. James, the Camino de Santiago is a popular walking path that leads to the cathedral of Santiago de Compostela in northern Spain. Here, the apostle St. James is said to be buried.
There are a number of different routes to the final destination -- these can take anywhere from a week to months. The French Way is one of the most popular and has been declared part of a UNESCO World Heritage Site.
It starts from St. Jean Pied de Port, is 780 kilometers long (485 miles) and takes on average a month to hike. The trail is well signposted, easy to follow and provides ample opportunity to sample local culture and enjoy small towns and rioja wine en route.
Getting there: Best time to go is in May, June or September, avoiding July and August when many Europeans take vacation. To start in St. Jean Pied de Port, fly to Paris, Biarritz or Pamplona and take a train.
Pilgrims' Way to Canterbury (England)
The route from London to Canterbury Cathedral, known as the Pilgrims' Way, became popular with pilgrims after the Archbishop of Canterbury Thomas Beckett was murdered in 1170 by King Henry II's knights.
Beckett quickly became known as a miracle maker and was later canonized.
The main pilgrim route that ran between Winchester and Canterbury is sadly no longer a viable walking trail due to traffic. The modern pilgrim can follow the St. Swithun's Way to Farnham and then the North Downs Way to Canterbury.
Walking the entire 180-kilometer (112 miles) route will give you approximately two weeks to enjoy the English countryside and get a glimpse of its history.
Getting there: Best time to go is April through October. Winchester is one hour from London by train.
Croagh Patrick (Ireland)
There are stunning views along the west of Ireland if you make the steep ascent up this 765-meter (2,509 feet) high mountain.
This is where St. Patrick, patron saint of Ireland, is said to have spent 40 days and nights praying and fasting and to have banished snakes from the country.
More than a million people from around the world make the journey every year to follow in St. Patrick's footsteps -- many of them barefoot.
Even though it takes only a couple of hours to reach the top, it's not an easy climb. At the peak, you can attend mass in a modern chapel or enjoy the views before making your way back down for a pint of Guinness in a local pub.
Hikers can also a walk along the 61-kilometer-long (38 miles) St. Patrick's Heritage Trail.
Getting there: Best time to go is April through September, but traditional pilgrimage days are the last Friday and Sunday of July, and August 15. Croagh Patrick is eight kilometers (five miles) from Westport town, which is accessible by both bus and train from Dublin and Galway.
Char Dham (India)
Char Dham refers to four pilgrimage sites in the Uttaranchal state at the foot of the Himalayas.
These sites are particularly important to Hindus, who aim to visit them at least once in their lifetime.
For the non-religious, this journey is an excellent way to learn more about Indian culture and tradition and to experience the natural beauty of the country.
More than 250,000 visitors from around the globe make the trip annually. Most of them start their journey in the temple town of Haridwar, while others leave from Rishikesh or Dehra Duhn, the capital of Uttaranchal.
Tradition dictates visiting the sites from east to west in the following order: Yamunotri, Gangotri, Kedarnath and Badrinath. Allow approximately two weeks to visit all four or visit one only in three or four days.
Getting there: Best time to go is May-June and September-October, avoiding monsoon season. Fly to New Delhi and take a train to Haridwar.
Editor's note: This story was originally published in April 2013. It was updated in October 2015.